Mechanism for retrieving a dummy block from an extrusion press

ABSTRACT

Mechanism for receiving a dummy block from an extrusion press comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press to a position below the dummy block so that the dummy block may fall into the retriever after the extrusion press is opened and means for retracting the retriever transversely of the press axis outwardly of the press thereby carrying the dummy block with it to a processing station.

United States Patent [72] inventor Andrew J.Grimes 2,728,453 12/1955 Tweatt 1 72/255(X) Phoenix, Ariz. 2,736,429 2/1956 Sejournet. 72/255(X) [21] Appl. No, 763,120 2,896,783 7/1959 Swanson... 72/255 [22] Filed Sept. 27, 1968 3,373,592 3/1968 Robra 1 1 1 72/255 [45] P nw J n 1, 1971 775,180 11/1904 Jones 1 1 214/23 [73] Assignee Reyn ld Me ls C mp ny 2,813,637 6/1952 Perry 214/85 Richmond, Va. 2,522,577 9/1950 Johnson 214/85 [54] MECHANISM FOR RETRIEVING A DUMMY BLOCK FROM AN EXTRUSION PRESS Primary ExaminerRichard J. Herbst Assistant Examiner-Michael .l. Keenan Attorney-Glenn, Palmer, Lyne, Gibbs & Thompson ABSTRACT: Mechanism for receiving a dummy block from an extrusion press comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press to a position below the dummy block so that the dummy block may fall into the retriever after the extrusion press is opened and means for retracting the retriever transversely of the press axis outwardly of the press thereby carrying the dummy block with it to a processing station.

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HIS ATTORNEYS MECHANISM FOR RETRIEVING A DUMMY BLOCK FROM AN EXTRUSION PRESS BACKGROUND OF THE INVENTION In an apparatus for extruding stock material from a billet it is customary to provide a dummy block within the extrusion cylinder between the ram and the billet. This dummy block protects the face of the ram from damage by the billet. These dummy blocks heretofore have been cumbersome to handle after being removed from the extrusion cylinder. A conventional method of removing these dummy blocks has been to grip the dummy block by the use of tongs thereby ensuring that the block remained in the desired orientation with respect to the extrusion cylinder. Such a manner of removing dummy blocks, while it may achieve the desired result, is expensive and time consuming. Accordingly, a more efficient apparatus for removing and ensuring the proper orientation of a dummy block once removed is needed in the industry.

SUMMARY This invention provides an apparatus to facilitate the expedient and efficient removal of a dummy block from the ex trusion cylinder and means to ensure that the dummy block does not become disoriented with respect to a fixed position, once removed, this necessitating further handling of the block before it can be recycled for reuse in the extrusion press.

The apparatus of this invention includes a mechanism for,

retrieving a dummy block from an extrusion press, comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation. The retriever preferably has a dummy block receiving chamber having opposed generally parallel sidewalls spaced apart a distance such that when the dummy block falls into the receiving chamber, with its opposed flat faces generally parallel to the sidewalls of the receiving chamber, it will be restrained against substantial tilting or turning. The receiving chamber may have an open bottom and means may be provided below the receiving chamber for preventing the dummy block from falling through the receiving chamber, so that the dummy block may roll on such means when the retriever is retracted. An elevator may be provided atop on which the dummy block may be positioned when the retriever is retracted together with means for raising the elevator to expel the dummy block from the receiving chamber.

Preferably, the retriever has a dummy block receiving chamber positionable below the dummy block when the retriever is projected inwardly of the press with means adapted to coact with the dummy block and press die, depending on the axial length of the dummy block, ensuring proper positioning of the receiving chamber below the dummy block. The retriever may be actuated and may have a dummy block receiving chamber positionable below the dummy block when the retriever is projected inwardly of the press and means are desirably provided correlating the position of the receiving chamber with the dummy block in a direction parallel to the press axis, while maintaining substantially constant the orientation of the receiving chamber. In a preferred form the retriever includes a flexible parallelogram linkage. The retriever may be actuated and spring means may be provided for urging the receiving chamber generally toward the press die to ensure the coacting of the positioning means with the dummy block and the press die when the retriever is projected inwardly of the press. Means including a torque bar may be provided urging the receiving chamber out of line with the remainder of the retriever and generally toward the press die to ensure coacting of the positioning means with the dummy block and press die when the retriever is projected inwardly of the press and straightening out of the retriever when the retriever is retracted outwardly of the press. The sidewall of the receiving chamber, remote from the press die, desirably extends upwardly well beyond the top of the sidewall closer to the press die so that, when the retriever is projected inwardly of the press, depending upon the axial dimension of the dummy block, either the side of the receiving chamber next the press die engages the press die, or, the upwardly extending wall of the receiving chamber, remote from the press die, engages the face of the dummy block remote from the press die.

In normal operation of an aluminum extrusion press the heated billet is introduced into the press in a position to be pushed (extruded) through the die with a dummy block behind the billet. The press ram acts against the dummy block, which in turn acts against the billet, so that the billet is extruded through the die cavity by the ram and interposed dummy block.

At the conclusion of the extrusion stroke the press is opened and the dummy block, which adheres to the butt (the end of the billet remaining in the press at the conclusion of the extrusion stroke), is dislodged from the butt by a laterally directed blow. The dummy block, which is circular, drops down and is intended to roll out of the press. However, on most occasions it becomes tilted or turned and remains lodged in the press and does not roll out and has to be removed by tongs.

The purpose of the present invention is to ensure uniform removal of the dummy block from the press upon each cycle.

I provide a mechanism for retrieving a dummy block from an extrusion press comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press to a position below the dummy block so that the dummy block may fall into the retriever and means for retracting the retriever transverse- Iy of the press axis outwardly of the press carrying the dummy block with it to retrieve the dummy block from the press. The retriever preferably has a dummy block receiving chamber having opposed generally parallel sidewalls spaced apart at a distance such that when the dummy block falls into the receiving chamber with its opposed flat faces generally parallel to the sidewalls of the receiving chamber, it will be restrained against substantial tilting or turning. The receiving chamber may have an open bottom and means may be provided below the receiving chamber preventing the dummy block from falling through the receiving chamber so that the dummy block may roll on such means when the retriever is retracted. An elevator may be provided atop on which the dummy block may be positioned when the retriever is retracted, together with means for raising the elevator to expel the dummy block from the receiving chamber.

Preferably, the retriever has a dummy block receiving chamber, positionable below the dummy block when the retriever is projected inwardly of the press, with means adapted to coact with the dummy block and press die, depending on the axial length of the dummy block, ensuring proper positioning of the receiving chamber below the dummy block. The retriever may be actuated and may have a dummy block receiving chamber positionable below the dummy block when the retriever is projected inwardly of the press and means are desirably provided correlating the position of the receiving chamber with the dummy block in a direction parallel to the press axis, while maintaining substantially constant the orientation of the receiving chamber. In a preferred form the retriever includes a flexible parallelogram linkage. The retriever may be actuated and spring means may be provided urging the receiving chamber generally toward the press die to ensure coacting of thepositioning means with the dummy block and press die when the retriever is projected inwardly of the press. Means including a torque bar may be provided urging the receiving chamber out of line with the remainder of the retriever and generally toward the press die to ensure coacting of the positioning means with the dummy block and press die when the retriever is projected inwardly of the press and straightening out of the retriever when the retriever is retracted outwardly of the press. The sidewall of the receiving chamber, remote from the press die, desirably extends upwardly well beyond the top of the sidewall closer to the press die so that, when the retriever is projected inwardly of the press, depending upon the axial dimension of the dummy block, either the side of the receiving chamber next the press die engages the press die, or, the upwardly extending wall of the receiving chamber remote from the press die engages the face of the dummy block remote from the press die.

Other details, objects and advantages of the invention will become apparent as the following description of a present preferred embodiment thereof proceeds.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings 1 have shown a present preferred embodiment of the invention in which FIG. 1 is an isometric view with portions broken away of a mechanism for retrieving a dummy block from an aluminum extrusion press, the retriever being shown in retracted position;

FIG. 2 is a view similar to FIG. 1 but showing the retriever in projected position;

FIG. 3 is a top plan view of the mechanism with portions broken away;

FIG. 4 is a side elevational view of the mechanism with portions broken away;

FIG. 5 is a diagram illustrating operation of the mechanism; and

FIGS. 6 and 7 are diagrams showing the press cylinder with the press ram therein near the beginning ofits stroke in FIG. 6 and at the end of its stroke in FIG. 7.

DESCRIPTION OF THE ILLUSTRATED EXEMPLARY EMBODIMENTS Referring now more particularly to the drawings, and first to FIGS. 6 and 7, there is shown diagrammatically the cylinder 2 of an aluminum extrusion press into which a heated billet 3 (FIG. 6) of aluminum or aluminum alloy is positioned to be pushed or extruded by the press ram 4 through a die 5 having a die cavity 6 so that the material of the billet is formed into an elongate product 7 having a uniform section determined by the shape of the die cavity 6. The dummy block 8 is interposed between the ram and the billet. At the end of the extrusion stroke a small portion 9 (FIG. 7) of the billet called the butt remains in the cylinder, the dummy block lying against the butt and generally adhering thereto.

At the end of the extrusion stroke the press is opened, the ram is retracted and the dummy block is dislodged from the butt. The butt is sheared off at the inner face of the die and removed, a new heated billet and dummy block are positioned between the retracted ram and the die and the press closes in readiness for the succeeding extrusion stroke. Everything described in the preceding paragraph and in the first sentence of this paragraph is conventional and well known to those skilled in the art so it is unnecessary to illustrate the details of the press; the description to follow and the accompanying drawings FIGS. 15 are confined to the mechanism for retrieving the dummy block.

My mechanism for retrieving a dummy block from an extrusion press comprises a dummy block retriever designated generally by reference numeral 10 which operates generally at right angles to the stroke of the press. When the press opens up at the end of an extrusion stroke the retriever 10, which has a dummy block receiving chamber 11 at its forward end, is advanced to a position with the receiving chamber 1] underneath the dummy block 8. The retriever 10 consists of a main element or body 12, which is outermost, the receiving chamber 11, which is innermost, and two spaced-apart parallel links 13 each hinged by a hinge having a vertical pintle 14 to the body 12 of the retriever at the outer end of the link and to the receiving chamber 11 at the inner end of the link. The links 13 thus act as a flexible parallelogram ensuring in and out movement of the receiving chamber 11 with the body 12 of the retriever but providing for sidewise shifting of the receiving chamber 11 relatively to the body 12 of the retriever while maintaining the receiving chamber in fixed orientation.

In FIG. 1 the retriever 10 is shown in its outer or retracted position. In FIG. 2 the retriever I0 is shown in its inner or projected position.

The in and out movement of the retriever is effected by suitable driving means including a motor 15 mounted on a fixed base 16 disposed outwardly of the retriever and a sprocket chain drive operatively connected with the motor and with the body of the retriever. The motor drives through reduction gearing a shaft 17 to which is fixed a sprocket 18. The body 12 of the retriever is guided by a rod 19 connected with the base 16 and having a plate 20 fixed to its inner end. A sprocket chain 21 meshes with the sprocket l8 and with a sprocket mounted on a bracket 22 carried by the plate 20. The sprocket chain is dead ended at both ends to the outer end plate 23 of the retriever body 12. Thus, operation of the motor 15 drives the retriever inwazrdly or outwardly depending upon the direction of rotation of the motor.

When the retriever I0 is in its retracted position as shown in FIG. I the plate 20 is disposed between the links 13 and serves to guide the links as the body 12 passes outwardly beyond the plate 20. Such guiding of the links ensures their outward movement following the path of the body 20 during the final stage of outward movement of the retriever. Upon inward movement of the retriever the links 13 pass beyond the plate 20 as shown in FIG. 2, but the plate 20 cooperating with the rod 19 always guides the retriever body 12.

The link 13 on the side of the retriever nearer the press die has a bracket 24 projecting generally in a direction toward the die. Pivotally connected with that bracket at 25 is a torque arm 26 which passes through a bore 27 in the outer end plate 23 of the retriever body 12 and also through a bore in the fixed base 16. The torque arm carries a first stop 28 outwardly of the fixed base which engages the fixed base upon predetermined inward movement of the retriever causing flexing of the parallelogram consisting of the links 13 to shift the receiving chamber 11 generally toward the press die relatively to the body 12 of the retriever while maintaining the receiving chamber in fixed orientation.

The torque arm 27 carries a second stop 29 fixed to the torque arm intermediate the bracket 24 on the link 13 on the side of the retriever nearer the press die and the outer end plate 23 of the retriever body 12 through which the torque arm passes and a compression coil spring 30 surrounds the torque arm between the second stop and the outer end plate 23. Upon outward movement of the retriever after the first stop, 28 moves away from the fixed base 16, the compression coil spring 30 is compressed between the second stop 29 and the outer end plate 23 causing flexing of the parallelogram to shift the receiving chamber back into line with the retriever body while continuing to maintain the receiving chamber in fixed orientation.

The receiving chamber has two parallel sidewalls 31 and 32 and an open bottomv The sidewall 32 remote from the press die, extends upwardly well beyond the top of the sidewall 31 closer to the press die. When the retriever is moved inwardly and the receiving chamber 11 is shifted generally toward the press die relatively to the body of the retriever, as above described, the receiving chamber is disposed underneath the dummy block 8 and, depending upon the axial length of the dummy block, either the side 31 of the receiving chamber next to the press die engages the press die, or, the upwardly extending wall 32 of the receiving chamber, remote from the press die, engages the face of the dummy block 8, remote from the press die. In either case the receiving chamber is disposed to receive the dummy block when it is dislodged from the butt 9 and to assure maintenance of the orientation of the dummy block, i.e., with its axis horizontal and generally parallel to the axis of the press. This is assured because the spacing apart of the sidewalls 31 and 32 of the receiving chamber 11 is such as always to receive the dummy block but the walls are close enough together to ensure against substantial turning of the dummy block. Also the spacing of the walls prevents tilting of the dummy block so that the dummy block when in the receiving chamber is in position with its axis horizontal and generally parallel to the axis of the press.

A dummy flap 33 forming a part of the press is raised to a position below and substantially closing the open bottom of the receiving chamber 11. The dummy block 8, when dislodged from the butt 9, falls by gravity between the walls of the receiving chamber and rests on the dummy flap 33. When the retriever is withdrawn, carrying the dummy block with it in the receiving chamber, the dummy block rolls upon the dummy flap 33 and upon a surface forming part of the press until it reaches a position atop an elevator 34 forming part of the press. At that point retraction of the retriever is completed and the elevator is raised and lifts the dummy block out of the receiving chamber 11 and delivers it into a guideway along which it rolls to a position remote from the press from which it may be returned for use in a subsequent cycle.

Thus, the dummy block retriever ensures maintaining consistent orientation of the dummy block and removal thereof from the press on each cycle and obviates the difficulty previously encountered of the dummy block becoming tilted or turned upon being dislodged from the butt necessitating its removal by tongs. I

While I have shown and described a present preferred embodiment of the invention it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied within the scope of the following claims.

lclaim:

l. Mechanism for retrieving a dummy block from an openable extrusion press in which the dummy block is disposed with its axis generally horizontal comprising a retriever for receiving the dummy block when the press is opened at the comple tion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press to a position below the dummy block when the dummy block is in the position it occupies at the completion of an extruding operation so that the dummyblock may fall while its axis remains generally horizontal into the retriever and means for retracting the retriever transversely of the press axis outwardly of the press carrying the dummy block with it to retrieve the dummy block from the press, the retriever having a dummy block receiving chamber having opposed generally parallel sidewalls spaced apart a distance such that when the dummy block falls into the receiving chamber with its opposed flat faces generally parallel to the sidewalls of the receiving chamber it will be restrained against substantial tilting or turning, the receiving chamber having an open bottom, and means below the receiving chamber preventing the dummy block from falling through the receiving chamber so that the dummy block may roll on such means when the retriever is retracted.

2. Mechanism for retrieving a dummy block from an openable extrusion press in which the dummy block is disposed with its axis generally horizontal comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press by movement in a substantially horizontal plane to a position below the dummy block when the dummy block is in the position it occupies at the completion of an extruding operation so that the dummy block may fall while its axis remains generally horizontal into the retriever and means for retracting the retriever transversely of the press axis outwardly of the press by movement in a substantially horizontal plane carrying the dummy block with it to retrieve the dummy block from the press, the press having an axis along which extrusion takes place upon operation of the press and the retriever being articulated and having a dummy block receiving chamber positionable below the dummy block when the retriever is projected inwardly of the press and means being provided correlating the position of the receiving chamber with the dummy block in a direction parallel to the press axis while maintaining substantially constant the angular position of the longitudinal axis of the receiving chamber relatively to the press axis.

3. Mechanism for retrieving a dummy block from an openable extrusion press in which the dummy block is disposed with its axis generally horizontal comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press to a position below the dummy block when the dummy block is in the position it occupies at the completion of an extruding operation so that the dummy block may fall while its axis remains generally horizontal into the retriever and means for retracting the retriever transversely of the press axis outwardly of the press carrying the dummy block with it to retrieve the dummy block from the press, the retriever having a dummy block receiving chamber positionable below the dummy block when the retriever is projecting inwardly of the press, and means adapted to coact with one of the dummy block and press die, depending on the axial length of the dummy block, ensuring proper positioning of the receiving chamber below the dummy block, the retriever being articulated and spring means being provided urging the receiving chamber generally toward the press die to ensure coacting of said means with one of the dummy block and press die when the retriever is projecting inwardly of the press.

4. Mechanism for retrieving a dummy block from an extrusion press as claimed in claim 1 including an elevator atop which the dummy block is positioned when the retriever is retracted and means for raising the elevator to expel the dummy block from the receiving chamber.

5. Mechanism for retrieving a dummy block from an extrusion press as claimed in claim 2 in which the retriever includes a flexible parallelogram linkage.

6. Mechanism for retrieving a dummy block from an extrusion press as claimed in claim 3 in which the retriever is articulated and means including a torque bar are provided urging the receiving chamber out of line with the remainder of the retriever and generally toward the press die to ensure coacting of said means with one of the dummy block and press die when the retriever is projected inwardly of the press and straightening out of the retriever when the retriever is retracted outwardly of the press.

7. Mechanism for retrieving a dummy block from an extrusion press as claimed in claim 3 in which the sidewall of the receiving chamber remote from the press die extends upwardly well beyond the top of the sidewall closer to the press die so that when the retriever is projected inwardly of the press, depending upon the axial dimension of the dummy block, either the side of the receiving chamber next the press die engages the press die or the upwardly extending wall of the receiving chamber remote from the press die engages the face of the dummy block remote from the press die. 

1. Mechanism for retrieving a dummy block from an openable extrusion press in which the dummy block is disposed with its axis generally horizontal comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press to a position below the dummy block when the dummy block is in the position it occupies at the completion of an extruding operation so that the dummy block may fall while its axis remains generally horizontal into the retriever and means for retracting the retriever transversely of the press axis outwardly of the press carrying the dummy block with it to retrieve the dummy block from the press, the retriever having a dummy block receiving chamber having opposed generally parallel sidewalls spaced apart a distance such that when the dummy block falls into the receiving chamber with its opposed flat faces generally parallel to the sidewalls of the receiving chamber it will be restrained against substantial tilting or turning, the receiving chamber having an open bottom, and means below the receiving chamber preventing the dummy block from falling through the receiving chamber so that the dummy block may roll on such means when the retriever is retracted.
 2. Mechanism for retrieving a dummy block from an openable extrusion press in which the dummy block is disposed with its axis generally horizontal comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press by movement in a substantially horizontal plane to a position below the dummy block when the dummy block is in the position it occupies at the completion of an extruding operation so that the dummy block may fall while its axis remains generally horizontal into the retriever and means for retracting the retriever transversely of the press axis outwardly of the press by movement in a substantially horizontal plane carrying the dummy block with it to retrieve the dummy block from the press, the press having an axis along which extrusion takes place upon operation of the press and the retriever being articulated and having a dummy block receiving chamber positionable below the dummy block when the retriever is projected inwardly of the press and means being provided correlating the position of the receiving chamber with the dummy block in a direction parallel to the press axis while maintaining substantially constant the angular position of the longitudinal axis of the receiving chamber relatively to the press axis.
 3. Mechanism for retrieving a dummy block from an openable extrusion press in which the dummy block is disposed with its axis generally horizontal comprising a retriever for receiving the dummy block when the press is opened at the completion of an extruding operation, means for projecting the retriever transversely of the press axis inwardly of the press to a position below the dummy block when the dummy block is in the position it occupies at the completion of an extruding operation so that the dummy block may fall while its axis remains generally horizontal into the retriever and means for retracting the retriever transversely of the press axis outwardly of the press carrying the dummy block with it to retrieve the dummy block from the press, the retriever having a dummy block receiving chamber positionable below the dummy block when the retriever is projecting inwardly of the press, and means adapted to coact with one of the dummy block and press die, depending on the axial length of the dummy block, ensuring proper positioning of the receiving chamber below the dummy block, the retriever being articulated and spring means being provided urging the receiving chamber generally toward the press die to ensure coacting of said means with one of the dummy block and press die when the retriever is projecting inwardly of the press.
 4. Mechanism for retrieving a dummy block from an extrusion press as claimed in claim 1 including an elevator atop which the dummy block is positioned when the retriever is retracted and means for raising the elevator to expel the dummy block from the receiving chamber.
 5. Mechanism for retrieving a dummy block from an extrusion press as claimed in claim 2 in which the retriever includes a flexible parallelogram linkage.
 6. Mechanism for retrieving a dummy block from an extrusion press as claimed in claim 3 in which the retriever is articulated and means including a torque bar are provided urging the receiving chamber out of line with the remainder of the retriever and generally toward the press die to ensure coacting of said means with one of the dummy block and press die when the retriever is projectEd inwardly of the press and straightening out of the retriever when the retriever is retracted outwardly of the press.
 7. Mechanism for retrieving a dummy block from an extrusion press as claimed in claim 3 in which the sidewall of the receiving chamber remote from the press die extends upwardly well beyond the top of the sidewall closer to the press die so that when the retriever is projected inwardly of the press, depending upon the axial dimension of the dummy block, either the side of the receiving chamber next the press die engages the press die or the upwardly extending wall of the receiving chamber remote from the press die engages the face of the dummy block remote from the press die. 